Method and means for cleaning articles



4 Sheets-Sheet 1 June 19, 1962 E. HAJOS METHOD AND MEANS FOR CLEANING ARTICLES Filed June 7, 1957 5 5 R w W R E 0 W T 8 I T I N A E w m X E k 6 5 1 w. A 5 5 1 V M k U W \6 l) M 15M FIG. 1

BY vow .June 19, 1962 E. HAJOS 3,039,842

METHOD AND MEANS FOR CLEANING ARTICLES INVENTOR. EUGENE HAJO5 AT TO KN'EY June 19, 1962 E. HAJQS 3,039,842

METHOD AND MEANS FOR CLEANING ARTICLES Filed June 7, 1957 4 Sheets-Sheet 3 7O 57 %W aka/WA ATTORMEY June 19, 1962 E. HAJOS METHOD AND MEANS FOR CLEANING ARTICLES Filed June 7, 1957 4 Sheets-Sheet 4 mqq Z SPWZOU h mb H3231 ntzjm INVENTOR. EUGENE: H AJOS ATTORN EYE United States Patent 3,039,842 METHOD AND MEANS FOR CLEANDIG ARTICLES Eugene Haios, Chicago, 111., assignor, by mesne assignments, to Hydraxtor Company, Skokie, 11]., a corporation of Illinois Filed June 7, 1957, Ser. No. 664,271 7 Claims. (Cl. 8--159) This invention relates generally to a cleaning method and apparatus, and more specifically to a source of acoustic energy incorporated therein.

Although the principles of the present invention may be included in various devices, a particularly useful application is made in washing and cleaning machines of the acoustic or supersonic type.

Others have provided a method and means employing acoustic energy for the washing of small volumes of articles. Certain inherent limitations in the apparatus employed have made it impractical to apply such apparatus or methods for washing a load of 200 to 400 pounds of clothes, such as handled by commercial Washing machines. For example, one such type employs magnetostrictive transducers which, in order to have a high resonant frequency, are inherently small. Thus a large number of conventional transducers would be required for a large commercial wash-ing machine. A second limitation lies in the fact that an extremely large electronic oscillator or a substantial quantity of conventional electronic oscillators would be necessary in order to drive the large number of transducers required. The inclusion of this large quantity of electronic equipment is uneconomical and impractical.

The present invention contemplates the use of acoustic energy at ultrasonic or supersonic frequencies. Whether the frequency is audible in fact or inaudible, is immaterial. However, While such a term of reference is used for lack of a more appropriate term, it is contemplated herein, in using these terms, to refer to the frequencies of pulsation or vibration which exceed 10,000 cycles per second. In this invention, ultrasonic pulsations are formed by the coaction of a rapidly rotating element with respect to another element, one of said elements having openings which are directed as desired. In the embodiment illustrated herein, such direction is substantially all directions lying in a single plane. Thus to subject the entire volume of the liquid and articles in the liquid to such pulsations, the third dimension of exposure is provided by translation or reciprocation of the transducer or source of acoustic energy in a direction transverse to the direction of movement or propagation of the vibrations or waves. Thus the entire volume of the liquid is scanned by the ultrasonic vibrations. While certain portions of the invention are illustrated in conjunction with a washing machine, it is to be understood that certain subcombinations of my invention may be utilized in other ultrasonic arts.

Accordingly, it is an object of the present invention to provide a washing machine which utilizes acoustictype energy having a frequency in excess of 10,000 cycles per second.

It is a further object of this invention to provide a machine which will cleanse the articles by use of ultrasonic acoustic energy and which will also extract Water from the cleansed articles.

It is a further object of this invention to provide a novel method of cleaning articles.

Yet another object of the instant invention is the provision of a method and means for economically applying ultrasonic energy to a relatively large volume of articles to be cleansed.

A still further object is the provision of novel features to a washing machine whereby a relatively large load may be conveniently handled and cleaned.

A still further object is the provision of a method and means for the production of ultrasonic acoustic-type pulsations or vibrations in a liquid.

Many other advantages, features and additional objects of the present invention will become manifest to those versed in the art upon making reference to the detailed description and the accompanying sheets of drawings in which a preferred structural embodiment incorporating the principles of the present invention is shown by way of illustrative example.

FIGURE 1 is a cross-sectional view of a washing machine constructed in accordance with the principles of my invention;

FIGURE 2 is a cross-sectional view of the machine of FIGURE 1 wherein the washing apparatus has been replaced by extracting apparatus;

FIGURE 3 is a sectional perspective view showing how a screen separator may be installed or removed from the washing machine;

FIGURE 4 is a cross-sectional view of an impellertype transducer shown schematically in FIGURE 1;

FIGURES 5 and 6 are detailed fractional views of the impeller of FIGURE 4; and

FIGURE 7 is a schematic flow diagram of a complete washing machine installation.

As shown on the drawings:

The principles of this invention are particularly useful when embodied in a washing machine assembly such as illustrated in FIGURE 1, generally indicated by the numeral 10. The machine 10 includes a supporting base 11 which typically rests on the floor or on a platform. The base 11 supports a tub 12, such as by a pair of trunnions 13, 13 which provide a pivotal support whereby the tub 12 may be rocked or pivoted with respect to the base 11. During normal operation, the machine '10 is in the position shown, and it is contemplated that it will be pivoted primarily for unloading the contents from the tub 12. At its upper end, the tub 12 has an opening 15 which is closed by a cover 16. The cover 16 is nestingly received by the tub 12 at the opening 15 and, if desired, may be adapted to form a water-tight connection therewith at its periphery 17. The cover 16 may be clamped to the tub 12, as by a clamping ring 18 which opens to receive the edge of the tub and the periphery of the cover as shown. Since it is contemplated that this invention will be utilized with relatively large loads of articles to be cleaned, the phy-ical size is such that it is preferable to provide means on the cover 16, here illustrated as being a plurality of hooks 19 to which a hoisting cable, chain or wire 20 may be secured. The wire 20 may be secured at its upper end to a hoist operating on a monorail, as indicated in FIGURE 2.

The cover 16, shown in FIGURE 1, carries a mechanical means generally indicated at 22 which includes a portion which extends downwardly therefrom into the tub 12 for immersion into a volume of cleaning liquid 23 therein. The means 22 includes principally a transducer 24, and if desired, a means to produce relative translational movement between the transducer 24 and the volume of liquid 23, here illustrated as being a plurality of fluid pressure actuators 25 for providing reciprocation of the transducer '24. The actuators 25 are of course fluidly' connected to a controlled fluid supply system for reciprocation, such system being shown schematically in FIG- URE 7 as a fluid line the details of which system are well known and do not form a part of the instant invention. The actuators 25 are supported by their cylinders to the cover 16 and may be further rigidified by a plurality of brackets 26. The actuators 25 are connected by their rods a to the transducer assembly 24 which is fitted with a steam inlet line 39, a steam return line 31 and a high pressure liquid line 32.

In order to prevent certain articles being cleaned, such as fabrics, from interfering with the reciprocation or translation of the transducer 24, it is preferable to include a screen-like tubular member 35 to space the articles being cleaned 39 from the region or zone in which the transducer 24 moves. The tubular member 35 also shown in FIG- URE 3, is held in the desired position by an annular supporting ring 36 which is provided with a plurality of hooks or loops 37 to which the Wire or cable 20 may be attached for raising or lowering by the hoist 21. In the form illustrated in FIGURES 1 and 3, the screen-like tubular member 35 is also provided with a plurality of perforated radially extending flanges 38 which serve to divide the inside of the tub 12 into a like number of compartments.

The tub 12 has a sump chamber 49 which is covered by a heavy screen 41 and to which chamber a sump pump may be attached for emptying the tub 12 of the cleaning liquid 23.

It is to be understood that the screen-like tubular member 35 in certain embodiments may be made integral or may be carried by either the tub 12 or the cover 16.

When the articles 39 of the fabric type have been cleaned as in a manner more fully explained herein, the clamp ring 18 may be loosened so that the cover 16 and the tubular screen-like member 35 may be removed. Thereafter, as shown in FIGURE 2, a second cover 45 may be nested in the opening 3.5 at the top of the tub 12. The cover 45, at its lower surface, supports a flexible diaphragm 46 which extends inwardly of the tub 12. A pressure inlet fitting indicated at 47 is provided so that compressed air or pressurized liquid may be led to a region 48 between the cover 45 and the diaphragm 46 so as to expand the diaphragm 46 in a direction indicated by the arrows so as to extract cleaning fluid from the articles 39 (shown in FIGURE 3). A dump valve 50 communicates with the space 48 for relieving the pressure or pumping out the liquid acting against the diaphragm 46 after extraction is completed. When the cover assembly 45 is so used, it is necessary for the clamping rings 18 to provide a force which reacts against the extracting force caused by the movement of the diaphragm 46. As clearly shown in FIGURE 2, the cover 45 is also provided with a plurality of lifting means 51 whereby the hoist 21 may raise the cover 45 using the cable 29.

Referring to FIGURE 4, there is shown a cross-sectional view of the transducer 24. The transducer includes a'supporting housing 69 which is secured to the rods of the actuators 2-5 so that the actuators 25 may raise or lower the transducer 24. Secured to the lower edge of the supporting housing 60 are a pair of supporting bases, viz. an upper supporting base 61, and a lower supporting base 62. In the form shown herein, the upper supporting base 61 supports a means for providing high speed rotary motion, generally indicated at 64. The means 64 may comprise an electric motor, a hydraulic motor, a pneumatic motor, an air turbine, or a steam turbine assembly, as illustrated. Thus, in this invention, any convenient means may be utilized for providing a source of high speed rotary motion. Therefore, the inclusion of a steam turbine in this drawing is by way of illustration and its structural details do not form a part of my invention. The steam inlet line 39 extends through the upper supporting base housing 61 which also serves to define an inlet manifold 63 for live steam which is directed againstt-he upper surface of a turbine wheel 65. After the steam has passed through the turbine wheel 65, it is collected by the lower supporting housing 62 which also serves to define a collection manifold 63 and which communicates with the steam return line 31. The turbine wheel 65 is carried by a shaft 66 which is bearingly supported within the housing 60. A governor 67 may also be included if desired. By

an appropriate use of grommets and seals at the upper part of housing 60, a liquid-tight connection is made by the various components with the housing 60 as shown so that when the transducer 24 is immersed in cleaning liquid, such liquid will not enter the upper portion of the transducer 24 which carries the means 64 for providing rotary power.

The shaft 66 is connected to a shaft 66 in driving relation. At the lower end of shaft 66, there is provided an impeller wheel 68 which is keyed at a point 69 to the shaft 66' and locked thereon by a pair of nuts 76. The lower supporting base housing 62 supports a tubular shaped housing 71 in depending relation thereto. The tubular housing 71 in turn dependingly supports an element 72 which extends about the impeller wheel 68. The shaft 66 is bearingly supported at a portion 73 by the tubular housing 71. A liquid-tight jacket 7'5 is sealingly carried about the element 72 and the lower end of the housing 6% to seal the several joints thus spanned from the entrance of cleaning liquid. The high pressure fluid line 32 is directed into a region partially defined by the tubular housing 71 and extending to the impeller or impeller wheel 68. The impeller 68 is provided with an annular groove 76 at its upper surface which groove communicates with the high pressure line 32. A plurality of passages 77, 78 extend from the groove 76 in a radial direction and terminate as a like number of outlets at the outer periphery of the impeller 68. The element 72 is provided with a plurality of openings 79 which register with the passages 77 and '78 and which communicate outwardly with the volume of liquid 23 in the tub 12. For purposes of clarity, the clearance between the impeller 68 and the element 72 has been greatly exaggerated in the drawing. As a practical matter, however, the clearance is extremely small so that in elfect a labyrinth seal is provided therebetween. The outer ends of the passages 77 and 78 are so spaced that an imperforate portion of the element 72 which lies between adjacent openings 79 instantaneously substantially fully blocks the outlet end or outer end of each of the passages 77 and 78 when the impeller 68 is rotated relative to the element 72. Thus it can be seen that the high pres sure source line 32 communicates with a chamber which is substantially sealed except for the passages 77 and 78 in the impeller 68. Suitable seals may also be provided to keep the cleaning liquid away from the bearings and from leaking out along the shaft 66'.

In a preferred embodiment of this invention, the openlugs 79 which communicate with the cleaning liquid 23 in the tub 12 are arranged in such a pattern so that their axes he substantially in a comrnon plane. Of course, any other desired pattern or configuration may be utilized if such is more advantageous in another embodiment.

Referring to FIGURES 5 and 6, further details of the impeller 68 and the element 72 are more clearly shown. For most advantageous impeller structure, it is desirable that the outer ends of the passages 77 and 78 be placed as closely together as possible, but with a spacing between such outer ends equal to at least one diameter of each such passage. When such passages are directed inwardl it can be seen that their inner ends would overlap. Accordingly, the inner ends of half of the passages have been upwardly disposed. If desired, the passages 77 and 78 may be directed at an angle with respect to a true radius of the impeller 63 so as to aid the flow of liquid from the central cavity 76 of the impeller 68 to the outer periphery of the element 72 and into the main tub 12. Likewise, if desired, the openings 79 may also be directed at an angle with respect to the passages 77 and 78 with which they register. When the passages 77, 78 and openings 79 are angled as indicated, a freer fluid flow occurs.

Referring to FIGURE 7, there is shown a how diagram for the washing machine and its subsidiary components. The machine includes the tub 12 into which a cleaning liquid is admitted. Thus, by opening a solenoid valve 9, hot water may be admitted which flows in the direction of the arrows into the tub 12. The valve would be moved to a closed position when the desired liquid level has been attained, for example that is vel shown in FIGURE 1. In this specific embodiment, the use of hot water has been illustrated. It is to be understood, however, that such showing is by way of illustration and not by way of limitation. It is apparent to those versed in the art that other cleaning fluids may, in certain embodiments, be even more efiicacious. The cleaning liquid is forced into the tub 12 by a pump 91, here shown to be a constant displacement circulating pump, by way of example. Since the hot water enters the pump at line pressure, the pump will draw more water from the line when the valve 90 is open than it will from the tub. When the water in the tub 12 has reached the level of the opening 79 in the transducer 24, the basic conditions essential for cleaning are attained. Normally the valve 90 is closed before the cleaning cycle is initiated. If desired, detergent or other material may be added to the volume of water 23 in the tub body as by means of a detergent feeder 92 under the control of a solenoid valve 93.

In commercial laundries, live steam is ordinarily available and therefore, this embodiment has been illustrated as including steam driven means for operating the impeller. Accordingly, the steam from the boiler is admitted to the steam turbine 64 through the line 30. Steam from the turbine at a lower pressure may be returned to the boiler, through line 31 or directed to other laundry apparatus, such as mangles, for utilization therein. The turbine 64 rotates the shaft 66' which rotates the impeller 68.

Referring again to FIGURE 4, when the impeller 68 is in the instantaneous position as shown, the high pressure liquid from the pump 91 enters the transducer via line 32 and flows through the plurality of passages 77 and 7 8, and outwardly through the openings 79 into the tub 1 2. An instant later, due to an increment of rotation of the impeller 68, the passages 77 and 7 8 are blocked by the imperforate portion between the openings 79, and hence the flow through the openings 79 is interrupted. An instant later, the impeller has been rotated by the means 64 so that the passages 77 and 78 are again unblocked, thus causing a sharp resumption or burst of flow through the passages 79, which flow is of a high velocity because of the pressure in the line 32. The sharp resumption typically produces a high energy shock wave of substantially annular form which travels at sonic velocity in the liquid.

In the form illustrated in FIGURE 5, there are approximately fifty passages in the impeller 58. Thus in one revolution, any one passage will be unblocked a total of fifty times by the various openings 79. If the turbine is caused to rotate at a speed of 12,000 rpm, the flow through each of the fifty passages is caused to cease and resume a total of 10,000 times per second. Thus the flow of liquid through each of the passages is periodically interrupted so that it occurs in pulses. Each pulse produces a vibratory flow or acoustic wave which passes in the liquid to impinge against the articles contained therein. The liquid is an excellent carrier of this acoustic wave which loosens, frees and drives out or purges the foreign matter from the article to be cleaned. This cleaning process is eifective when the frequency of the pulses or vibrations reaches 10,000 cycles per second or higher. Ordinarily, the frequency range between 10,000 and 30,000 cycles per second will be utilized. However, it is to be understood that the 30,000 cycles per second should not be construed as being an upper limit.

Since these vibrations have the property of travelling in a straight line, the vibrations Will lie substantially in the plane or pattern defined by the openings 79. Thus, with the transducer 24 centrally located in the tub 12, the vibrations pass outwardly to the outer edges of the tub. In order to expose all of the articles in the tub to the ultrasonic pulsations, it is therefore preferable that there be a relative movement between the pulsation and the articles, such relative movement being in a direction transverse to the plane in which the pulsations themselves are moving. Accordingly, a relative movement therebetween may be provided by the fluid pressure actuators 25, here shown as comprising a means for reciprocating the transducer '24 vertically within the screen-like tubular member 35. Thus by providing relative movement between the plane or pattern in which the waves are propagated and the articles to be cleaned, a scanning action takes place, which thereby exposes all of the articles in the tub 12 to the purging action of the pulsating flow.

Referring again to FIGURE 7, it can be seen that the pump 91 comprises a means for providing a pressurized supply of liquid. This supply may be wholly independent of the liquid in the tub and may even comprise a different liquid, so lOng as it is compatible with the function to be performed. However, in this particular embodiment, a means 95 here shown as comprising a pipe, has been provided for returning the liquid from the tub to the pump- 91, whereby it may be recirculated. If desired, a filter and cleaner 98 may be included in pipe 95. Thus the high pressure line 32 in cooperation with the line 95, the pump 91 and the transducer 24, comprises a means for returning the liquid which is recirculated to a region below the surface of the volume of cleaning liquid 23.

Thus by this invention, a method and means has been provided wherein articles to be cleaned are immersed in a cleaning liquid in a tub after which a rapidly pulsating How of liquid is directed in all directions in a plane against the articles at such a frequency as to comprise ultrasonic acoustic vibrations which purge the articles of foreign matter. Relative movement between the articles and the plane in which the flow pulsations lie is also provided, for example by reciprocation, so as to thoroughly scan or expose all of the articles in the container to the cleansing action of the waves. Thus also, if desired, a portion of the liquid in the tub may be continually withdrawn and caused to reenter at a point below the surface of liquid through a means which imparts flow pulsations to such portion.

Also a novel ultrasonic transducer has been provided wherein high pressure liquid is forced into a pattern of outlets thereby causing a liquid fiow therethrough which flow is periodically blocked and unblocked at a frequency of such magnitude as to cause the ultrasonic functions to take place. Such a method may be carried out by means of an impeller or first element 68 which has generally radially extending passages, one end of each of which, for example the inner ends, is pressurized while the outer end of each confronts a second element having a plurality of openings aligned with the passages and communicating with the liquid in the tub. One of these elements thus is rotated at a high speed with respect to the other so as to periodically block and unblock the flow of liquid through the passages.

It is to be further understood that the number of passages in the impeller may be varied, higher frequencies being obtained when the number is increased, for a given speed of revolution.

Although various minor modifications might be suggested by those versed in the art, it should be understood that I wish to embody within the scope of the patent warranted hereon all such embodiments as reasonably and properly come within the scope of my contribution to the art.

I claim as my invention:

1. A washing machine comprising in combination: a tub for receiving articles to be cleaned and the cleaning liquid; a transducer means; and means for reciprocating said transducer means in the liquid in a fixed reciprocation axis; said transducer means being adapted to form acoustic waves in the liquid at an ultrasonic frequency and to radiate each of said waves substantially in an annular form substantially normal to and concentric with said reciprocation axis, whereby each of said waves is movable at once in all radial directions from said axis for engaging articles radially spaced in any direction from said axis While the articles are immersed in the liquid in said tub.

2. A washing machine comprising in combination: a tub for receiving articles to be cleaned and the cleaning liquid; a screen-like tubular member disposed in said tub; a transducer means disposed Within said screen-like tubular member; and means for reciprocating said transducer means in the liquid in a fixed reciprocation axis parallel to the axis of said screen-like tubular member; said transducer means being adapted to form acoustic Waves in the liquid at an ultrasonic frequency and to radiate each of said Waves substantially in an annular form substantially normal to and concentric with said reciprocation axis, and through said screen-like tubular member, whereby each of said Waves is movable at once in all radial directions from said axis for engaging articles radially spaced in any direction from said axis by said tubular member while the articles are immersed in the liquid in said tub.

3. A Washing machine comprisng in combination: a tub for receiving cleaning liquid, said tub having an opening for receiving articles to be cleaned in the liquid; a cover for said opening; a screen-like tubular member disposed in said tub; a transducer means disposed within said screen-like tubular member; and means supported solely by said cover and operative to support and reciprocate said transducer means Within said screen-like tubular member in the liquid in a fixed reciprocation axis, and comprising the sole support means for said transducer; said transducer means being adapted to form acoustic waves in the liquid at an ultrasonic frequency and to radiate each of said Waves substantially in an annular form substantially normal to and concentric with said reciprocation axis, whereby each of said waves is movable at once in all radial directions from said axis for engaging articles radially spaced in any direction from said axis by said tubular member While the articles are immersed in the liquid in said tub.

4. A washing machine comprising in combination; a tub for receiving articles to be cleaned and the cleaning liquid; a transducer means in the liquid; means supported by said tub for moving said transducer means relatively to the articles along a fixed path; said transducer means being adapted for forming and discharging over 1 0,000 one-way bursts of liquid flow per second directly against a point on an article in the liquid in said tub, each of said bursts being substantially in an angular form normal to and concentric With said fixed path, for scanningly exposing all parts of the articles in said tub to said bursts of 110W, for thereby loosening and purging foreign matter from the articles.

5. A method of cleaning a quantity of articles supersonically comprising the steps of: immersing the articles in a volume of cleaning liquid; imparting a pattern of acoustic vibrations at an ultrasonic frequency to the volume of liquid, each vibration being substantially in an annular form; and reciprocating said pattern in the volume of liquid along an axis concentric with said annular pattern for completely subjecting the articles immersed in the volume of liquid to said vibrations so that any foreign matter in the articles is cleansed therefrom.

6. A method of cleaning a quantity of articles supersonically comprising the steps of: immersing the articles in a volume of cleaning liquid; imparting a pattern of acoustic vibrations at an ultrasonic frequency to the volume of liquid, each vibration being substantially in an annular form; and imparting a relative movement between the articles and said pattern in a direction parallel to an axis concentric with said annular pattern for completely subjecting the articles immersed in the volume of liquid to said vibrations so that any foreign matter in the articles is cleansed therefrom.

7. A method of cleaning a quantity of articles comprising the steps of: immersing the articles in a volume of liquid; imparting over 10,000 one-Way bursts of flow of liquid per second directly against a point on an article in the volume of cleaning liquid, each of said bursts being in a pattern of substantially annular form; and imparting a relative movement between the articles and said pattern in a direction parallel to an axis concentric with said annular pattern for completely subjecting all parts of the articles immersed in the volume of liquid to said flow bursts, thereby freeing and driving out any foreign matter in the articles.

References Cited in the file of this patent UNITED STATES PATENTS 111,176 Churchman Jan. 24, 1871 597,716 Hwass Jan. 25, 1898 1,847,665 Perkins et a1. Mar. 1, 1932 2,147,302 Lang Feb. 14, 1939 2,421,242 Clark May 27, 1947 2,468,538 Beniolf Apr. 26, 1949 2,468,550 Fruth Apr. 26, 1949 2,500,008 Richardson Mar. 7, 1950 2,559,864 Firth July 10, 1951 2,560,728 Lee July 17, 1 951 2,650,872 Goldwasser Sept. 1, 1953 2,659,223 Karcher Nov. 17, 1953 2,693,943 Fowle Nov. 9, 1954 2,714,303 Bodman Aug. 2, 1955 2,776,558 Vang Jan. 8, 1957 2,816,429 Kurlancheek Dec. 17, 1957 2,824,438 Candor Feb. 25, 1958 2,882,706 Brucken Apr. 21, 1959 FOREIGN PATENTS 214,553 Germany Oct. 11, 1909 1,002,300 France Oct. 31, 1951 

5. A METHOD OF CLEANING A QUANTITY OF ARTICLES SUPERSONICALLY COMPRISING THE STEPS OF: IMMERSING THE ARTICLES IN A VOLUME OF CLEANING LIQUID; IMPARTING A PATTERN OF ACOUSTIC VIBRATIONS AT AN ULTRASONIC FREQUENCY TO THE VOLUME OF LIQUID, EACH VIBRATION BEING SUBSTANTIALLY IN AN ANNULAR FORM; AND RECIPROCATING SAID PATTERN IN THE VOLUME OF LIQUID ALONG AN AXIS CONCENTRIC WITH SAID ANNULAR 